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You searched for: Journal name Powder technology Remove constraint Journal name: Powder technology Publication year rev 7985-2015 Remove constraint Publication year rev: 7985-2015 Source 2015 v.272 Remove constraint Source: 2015 v.272
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1. Application of quadrature-based uncertainty quantification to the NETL small-scale challenge problem SSCP-I

Author:
X. Hu; A. Passalacqua; R.O. Fox
Source:
Powder technology 2015 v.272 pp. 100-112
ISSN:
0032-5910
Subject:
fluidized beds; models; powders; probability distribution; uncertainty
Abstract:
... Non-intrusive quadrature-based uncertainty quantification with reconstruction of the distribution of the system response is introduced and applied to the simulation of dense fluidized beds. This approach relies on the conditional quadrature method of moments (CQMOM) to generate a set of samples of the distribution of multiple uncertain parameters of the model. The moments of the system response ar ...
DOI:
10.1016/j.powtec.2014.11.030

2. Axial solids flow structure in a high density gas–solids circulating fluidized bed downer

Author:
Chengxiu Wang; Chunyi Li; Jesse Zhu
Source:
Powder technology 2015 v.272 pp. 153-164
ISSN:
0032-5910
Subject:
fluidized beds; optical fibers; powders; preferential flow
Abstract:
... Axial flow behaviors are investigated with an optical fiber probe using FCC particles at extremely high solids circulation rates up to 700kg/m²s and superficial gas velocity ranging from 3–7m/s in a laboratory-scale downer system. Results show that axial distributions of particle velocity and solids holdup are significantly affected by the operating conditions. Superficial gas velocity is the pred ...
DOI:
10.1016/j.powtec.2014.11.041

3. CFD simulation via conventional Two-Fluid Model of a circulating fluidized bed riser: Influence of models and model parameters on hydrodynamic behavior

Author:
Mukesh Upadhyay; Jong-Ho Park
Source:
Powder technology 2015 v.272 pp. 260-268
ISSN:
0032-5910
Subject:
fluidized beds; hydrodynamics; physical models; powders; prediction; simulation models; viscosity
Abstract:
... A two-dimensional (2D) numerical simulation of gas–solids flow in a circulating fluidized bed riser was performed based on the Two-Fluid Model (TFM). In this model, the kinetic theory of granular flows (KTGF) was used to solve gas–solids flow behavior. Despite several published studies, the selection of proper wall boundary conditions (BC) and the appropriate closure model to simulate riser flow r ...
DOI:
10.1016/j.powtec.2014.12.011

4. CFD simulations to study parameters affecting dust explosion venting in silos

Author:
Alberto Tascón; Pedro J. Aguado
Source:
Powder technology 2015 v.272 pp. 132-141
ISSN:
0032-5910
Subject:
dust; explosions; fluid mechanics; powders; silos
Abstract:
... Vented dust explosions in a 16.3m³ silo were simulated using a commercial CFD program. Simulations were carried out for vent panels without inertia and for a silo roof acting as a venting device, with inertia. For the latter, the influence of several parameters on the pressures generated was studied, including characteristics of the initial dust cloud, size and position of the dust cloud, and igni ...
DOI:
10.1016/j.powtec.2014.11.031

5. CFD-PBM modeling polydisperse polymerization FBRs with simultaneous particle growth and aggregation: The effect of the method of moments

Author:
Ya Yao; Jun-Wei Su; Zheng-Hong Luo
Source:
Powder technology 2015 v.272 pp. 142-152
ISSN:
0032-5910
Subject:
equations; hydrodynamics; models; particle size distribution; polymerization; powders; prediction
Abstract:
... Real solid systems in polymerization fluidized bed reactors (FBRs) are characterized by wide particle size distributions that change continuously due to particle micro-behavior, growth and aggregation, etc. Simulations of such gas–solid flow hydrodynamics require the solution of a coupled computational fluid dynamics (CFD)-population balance equation (PBE) model, i.e. the CFD-PBM. Therefore, the a ...
DOI:
10.1016/j.powtec.2014.11.037

6. Caking and adhesion free energy of maltitol: Studying of mechanism in adhesion process

Author:
Mingyang Chen; Songgu Wu; Weiwei Tang; Junbo Gong
Source:
Powder technology 2015 v.272 pp. 235-240
ISSN:
0032-5910
Subject:
Gibbs free energy; adhesion; capillarity; contact angle; ethanol; ethyl acetate; ethylene glycol; liquids; maltitol; methanol; particle size distribution; powders; screening
Abstract:
... Caking is a common phenomenon of maltitol that causes problems of separation, processing and transportation. To study the mechanism of caking, method of capillary rise was used to measure the contact angles between maltitol particles and relevant liquids. Based on the calculation of adhesion free energy of maltitol particles in different liquids by Lifshitz–van der Waals acid-base theory, the rela ...
DOI:
10.1016/j.powtec.2014.12.012

7. Combined small- and wide-angle X-ray scattering studies on oxide-supported Pt nanoparticles prepared by a CVS and CVD process

Author:
Xiaoai Guo; Kun Gao; Alexander Gutsche; Martin Seipenbusch; Hermann Nirschl
Source:
Powder technology 2015 v.272 pp. 23-33
ISSN:
0032-5910
Subject:
X-ray diffraction; aluminum oxide; atmospheric pressure; catalysts; crystallites; databases; fractal dimensions; mixing; models; nanoparticles; powders; quantitative analysis; silica; surface roughness; titanium dioxide; transmission electron microscopy; wide-angle X-ray scattering
Abstract:
... Various model oxide-supported metal catalyst particles (Pt nanodots supported on silica, titania and alumina) prepared by a CVS/CVD process at atmospheric pressure have been studied by using a self-developed SAXS and WAXS laboratory system. It has been shown that simultaneous SAXS and WAXS analyses offer a structural insight into the complexity of the supported metal catalysts, allowing quantitati ...
DOI:
10.1016/j.powtec.2014.11.028

8. Effect of powder densities, particle size and shape on mixture quality of binary food powder mixtures

Author:
Pooja Shenoy; Maxime Viau; Kristel Tammel; Fredrik Innings; John Fitzpatrick; Lilia Ahrné
Source:
Powder technology 2015 v.272 pp. 165-172
ISSN:
0032-5910
Subject:
bulk density; ingredients; mixing; oregano; particle size; powders; prototypes; thyme
Abstract:
... Particle size and density are two important parameters which affect the mixture homogeneity of powder mixtures. In this study several types of food powders with different particle sizes and poured bulk densities were chosen for the binary powder mixing trials. In each type of binary mixture salt was one of the main ingredients, hence conductivity analysis was performed on the mixtures and coeffici ...
DOI:
10.1016/j.powtec.2014.11.023

9. Effects of nanoparticle migration and asymmetric heating on mixed convection of TiO2–H2O nanofluid inside a vertical microchannel

Author:
F. Hedayati; G. Domairry
Source:
Powder technology 2015 v.272 pp. 250-259
ISSN:
0032-5910
Subject:
convection; models; nanofluids; nanoparticles; powders; temperature profiles; titanium dioxide; viscosity; water
Abstract:
... The effects of nanoparticle migration on mixed convection of titania/water nanofluid inside a vertical microchannel have been investigated numerically via Runge–Kutta–Fehlberg method. A modified two-component heterogeneous model is employed for the nanofluid in the hypothesis that the Brownian motion and the thermophoresis are the only responsible mechanisms for nanoparticle migration. Because of ...
DOI:
10.1016/j.powtec.2014.12.003

10. Evaluation of nanoparticle aggregate morphology during wet milling

Author:
Seongho Jeon; Thaseem Thajudeen; Christopher J. Hogan
Source:
Powder technology 2015 v.272 pp. 75-84
ISSN:
0032-5910
Subject:
aluminum oxide; fractal dimensions; hydrodynamics; industry; nanoparticles; powders; surfactants; titanium dioxide; viscosity; wet milling
Abstract:
... Recently developed wet mills (bead mills) have been shown capable of dispersing nanoparticle aggregates into primary particles in suspension, even with nanoparticles with primary particle radii as small as 5nm and at high nanoparticle volume fractions (>1%). However, to date what has not been examined is the change in aggregate morphology during milling itself, i.e. it is not clear if wet milling ...
DOI:
10.1016/j.powtec.2014.11.039

11. Influences of particle size, ultraviolet irradiation and pyrolysis temperature on stable free radicals in coal

Author:
Jiaxun Liu; Xiumin Jiang; Jun Shen; Hai Zhang
Source:
Powder technology 2015 v.272 pp. 64-74
ISSN:
0032-5910
Subject:
carbonization; coal; electron paramagnetic resonance spectroscopy; free radicals; gasification; irradiation; liquefaction; particle size; powders; pyrolysis; sediments; temperature; ultraviolet radiation
Abstract:
... Free radicals play an important part in coal utilization, such as carbonization, gasification, liquefaction and pyrolysis processes. The diagenesis of organic sediment, pyrolytic reactions during metamorphosis and radiolysis are the three possible geneses of stable free radicals in coal. The influences of different origins on the nature of free radicals and their subsequent behaviors during the co ...
DOI:
10.1016/j.powtec.2014.11.017

12. Interparticle interactions and lacunarity of mechano-chemically activated fly ash

Author:
Akshata G. Patil; A.M. Shanmugharaj; S. Anandhan
Source:
Powder technology 2015 v.272 pp. 241-249
ISSN:
0032-5910
Subject:
Fourier transform infrared spectroscopy; X-radiation; X-ray diffraction; aluminum; crystallites; ethyl acetate; fluorescence; fly ash; iron oxides; magnetic separation; milling; oxygen; particle size; powders; silicon; spectral analysis; surface area; surfactants
Abstract:
... A class F fly ash was subjected to high-energy ball milling-induced mechano-chemical activation aided by a surfactant. The resultant nanostructured fly ash was characterized by various techniques. X-ray fluorescence results showed that the amount of iron oxide was reduced from 4.39% to 2.75% after pre-treatment of fly ash by magnetic separation. Ethyl acetate as the milling medium, a ball to powde ...
DOI:
10.1016/j.powtec.2014.12.006

13. Investigating the conveying mechanism of particulate plugs with stationary layers

Author:
Semion Shaul; Haim Kalman
Source:
Powder technology 2015 v.272 pp. 322-331
ISSN:
0032-5910
Subject:
bulk density; conveyors; energy; models; powders; prediction
Abstract:
... This paper presents an investigation into pneumatic conveying mechanism of particulate plugs with stationary layers. A plug flow regime may exist in pneumatic conveying systems operating with high-pressure gradients and low gas velocities. The most significant advantages of transporting particulate materials in a plug form is low energy consumption, low particle attrition and low pipe erosion. How ...
DOI:
10.1016/j.powtec.2014.12.004

14. Investigation of influence of process variables on mechanical strength, size and homogeneity of pharmaceutical granules produced by fluidised hot melt granulation

Author:
Chirangano Mangwandi; N.A. Zainal; Liu JiangTao; Y. Glocheux; Ahmad B. Albadarin
Source:
Powder technology 2015 v.272 pp. 173-180
ISSN:
0032-5910
Subject:
active ingredients; air; air temperature; empirical models; granules; lactose; melting; methylene blue; powders; strength (mechanics)
Abstract:
... The overall aim of the project was to study the influence of process variables on the distribution of a model active pharmaceutical ingredient (API) during fluidised melt granulation of pharmaceutical granules with a view of optimising product characteristics. Granules were produced using common pharmaceutical excipients; lactose monohydrate using poly ethylene glycol (PEG1500) as a meltable binde ...
DOI:
10.1016/j.powtec.2014.11.042

15. Micromeritic properties and instrumental analysis of physical mixtures and solid dispersions with adsorbent containing losartan: Comparison of dissolution-differentiating factors

Author:
Thanh-Huyen Tran; Chulhun Park; Taehee Kang; Young-Joon Park; Euichaul Oh; Beom-Jin Lee
Source:
Powder technology 2015 v.272 pp. 269-275
ISSN:
0032-5910
Subject:
adsorbents; adsorption; crystal structure; differential scanning calorimetry; dispersions; drugs; energy-dispersive X-ray analysis; evaporation; grinding; hydrogen bonding; pH; particle size; porosity; potassium; powders; scanning electron microscopy; silica; solvents; surface area; water solubility; wettability
Abstract:
... Micromeritic properties and instrumental analysis of physical mixtures (PM) and solid dispersions (SD) with colloidal silicon dioxides (Aerosils) as adsorbents containing losartan potassium (LST) were investigated to explain the dissolution-differentiating factors. LST was chosen as a poorly water-soluble drug in acidic low pH conditions. The SD of LST with an adsorbent (1:1) was prepared by the s ...
DOI:
10.1016/j.powtec.2014.12.007

16. Numerical study of a lab-scale double slot-rectangular spouted bed with the parallel CFD–DEM coupling approach

Author:
Shiliang Yang; Kun Luo; Ke Zhang; Kunzan Qiu; Jianren Fan
Source:
Powder technology 2015 v.272 pp. 85-99
ISSN:
0032-5910
Subject:
equations; hydrodynamics; models; powders; turbulent flow
Abstract:
... The hydrodynamics of a three-dimensional double slot-rectangular spouted bed with two uniform chambers and two parallel slots are numerically studied by means of the parallel CFD–DEM coupling approach. In the coupling framework, the gas flow is described using the Navier–Stokes equations while the particles are tracked with the discrete element method. The start-up procedure and the typical flow s ...
DOI:
10.1016/j.powtec.2014.11.035

17. Photocatalyst ZnO-doped Bi2O3 powder prepared by spray pyrolysis

Author:
Chin-Yi Chen; Jui-Chung Weng; Jing-Heng Chen; Shih-Hsin Ma; Kun-Huang Chen; Tzyy-Leng Horng; Chien-Yie Tsay; Chi-Jung Chang; Chung-Kwei Lin; Jerry J. Wu
Source:
Powder technology 2015 v.272 pp. 316-321
ISSN:
0032-5910
Subject:
crystal structure; crystallites; irradiation; nanocrystals; photocatalysis; photocatalysts; powders; pyrolysis; surface area; temperature; titanium dioxide; zinc oxide
Abstract:
... In the present study, nanocrystalline photocatalyst Bi2O3 powders with various ZnO additions were synthesized by spray pyrolysis at 600 (SP600) and 700°C (SP700). The Bi2O3 powder converted from a monoclinic α phase to a tetragonal β phase at pyrolysis temperatures ≥600°C. The crystallinity of the SP powder increased with the increase in pyrolysis temperature. The morphology of the SP powders was ...
DOI:
10.1016/j.powtec.2014.11.036

18. Reducing cyclone pressure drop with evasés

Author:
P. A. Funk
Source:
Powder technology 2015 v.272 pp. 276-281
ISSN:
0032-5910
Subject:
air; cost estimates; cyclone separators; diffusers; emissions; energy; energy costs; fans (equipment); operating costs; pressure
Abstract:
... Cyclones are widely used to separate particles from gas flows and as air emissions control devices. Their cost of operation is proportional to the fan energy required to overcome their pressure drop. Evasés or exit diffusers potentially could reduce exit pressure losses without affecting collection efficiency. Three rectangular evasés and a radial evasé with a variable opening were tested on two c ...
Handle:
10113/60595
DOI:
10.1016/j.powtec.2014.12.019

19. Riser hydrodynamic study with different Group B powders

Author:
Sofia S. Rodrigues; A. Forret; F. Montjovet; M. Lance; Th. Gauthier
Source:
Powder technology 2015 v.272 pp. 300-308
ISSN:
0032-5910
Subject:
glass; hydrodynamics; momentum; particle size; powders; sand
Abstract:
... Experiments were conducted in a large cold flow CFB unit (18m long riser and 30cm in diameter) with three Group B powders. Sand, glass beads and a metal ore, with similar particle size, were used to study the impact of particle density and sphericity. The impact of particle nature on the riser hydrodynamics was investigated at similar operating conditions. Resulting axial pressure profiles are ver ...
DOI:
10.1016/j.powtec.2014.12.014

20. Segregation of titanium powder with polydisperse size distribution: Spectral and correlation analyses

Author:
Pawel Klisiewicz; John A. Roberts; Nicholas A. Pohlman
Source:
Powder technology 2015 v.272 pp. 204-210
ISSN:
0032-5910
Subject:
cost effectiveness; equipment; manufacturing; metallurgy; mixing; powders; titanium
Abstract:
... Additive manufacturing with powder metallurgy is becoming a popular and cost effective process due to improvements in powder availability and the ability to produce a part close to the desired net shape. Because the particles have a variety of shapes and sizes, the flow of titanium powder may be hindered if it is not uniformly mixed, resulting in poor quality end products. Understanding how titani ...
DOI:
10.1016/j.powtec.2014.11.029